1. Field of the Invention
The present invention relates to a semiconductor manufacturing device. More particularly, the present invention relates to an apparatus for cutting a wafer along a back side of a wafer.
2. Description of the Related Art
In general, semiconductor manufacturing may be divided into three processes. These processes are semiconductor wafer fabrication, package assembly and testing. Integrated circuits and devices are formed on a wafer during the semiconductor wafer fabrication process. After this process, the wafer is separated into diced chips, and then each diced chip is assembled into a package during the package assembly process.
Conventionally, dicing a wafer is accomplished by mounting the wafer on a chuck table and sawing the wafer using a diamond sawing blade. In the conventional dicing process, because the dicing process is progressed along a scribe line on a front side of a wafer, the side on which a semiconductor chip is formed, circuits of the semiconductor chip may be damaged by chippings generated during the dicing process. Additionally, wire bonding defects may be caused by silicon debris, which is not removed by a cleaning liquid, and which may adhere to an electrode pad.
In an attempt to solve these problems, a conventional method disclosed sawing along a back side of the wafer. According to this conventional method, a detector irradiates infrared rays that penetrate from the back side of the wafer to the front side of the wafer to recognize the semiconductor chip shape on a front side of the wafer. After recognition, the dicing process is performed. By using this conventional method of sawing along the back side of the wafer, some of the aforementioned problems may be solved. However, there is a disadvantage associated with using this conventional method since the semiconductor chip shape on the front side is recognized through the back side of the wafer, the recognition efficiency may be lower than direct recognition of the front side of the wafer. Direct recognition of the front side of the wafer reduces cutting defects that may occur due to misalignment of the sawing blade when recognition is performed from the back side of the wafer.
According to a feature of an embodiment of the present invention, there is provided an apparatus for cutting a wafer along a back side of the wafer that directly recognizes the semiconductor chip shape formed on a front side of the wafer.
According to an aspect of an embodiment of the present invention, an apparatus for cutting a wafer is provided which includes a chuck table, in which a hole is formed, wherein a wafer is mounted on the chuck table with a front side of the wafer facing down, a camera installed under the hole of the chuck table for recognizing the semiconductor chip shape of the front side of the wafer exposed through the hole, a sawing blade for cutting a back side of the wafer mounted on the chuck table, and a controller electrically connected to the chuck table, the camera and the sawing blade for controlling the driving of the chuck table, the camera and the sawing blade, wherein the controller drives the sawing blade to cut the wafer after the controller properly aligns the location of the wafer to the sawing blade by moving the chuck table according to information regarding the wafer directly recognized by the camera.
Preferably, the diameter of the hole of the chuck table is in the range of approximately 5-10 cm.
These and other features and aspects of the present invention will be readily apparent to those of ordinary skill in the art upon review of the detailed description that follows.